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Objective To observe the effects of acupoint catgut embedding therapy on body mass,lipid metabolism,serum leptin and mRNA and protein expressions of hypothalamic leptin receptor(LepR)-mediated Janus kinase 2(JAK2)/signal transducer and activator of transcription 3(STAT3)pathway in rats with diet-induced obesity(DIO).Methods Forty male SD rats were randomly divided into 10 in normal group and 30 in modeling group.A high-fat diet was used to establish the DIO rat model.After successful modeling,the modeled rats were randomly divided into the model group,the acupoint catgut embedding group and the acupoint catgut embedding + AG490(JAK2/STAT3 pathway blocker)group,with 10 rats in each group.The acupoint catgut embedding group and the acupoint catgut embedding + AG490 group were embedded on day(s)1,8,15 and 22 after successful modeling,the acupoints were selected from the Zhongwan(RN12),Shuidao(ST28),Tianshu(ST25),Pishu(BL20),Weishu(BL21),Sanjiaoshu(BL22)with a total of 4 treatments,and the acupoint catgut embedding + AG490 group was injected intraperitoneally with 1 mg/kg of AG490 every day during the treatment period;the normal group and the model group were only grasped and fixed.Body mass was measured before and after treatment.Lipid metabolism indexes of triglyceride(TG),total cholesterol(TC),low-density lipoprotein cholesterol(LDL-C),high-density lipoprotein cholesterol(HDL-C),and serum leptin levels were measured after treatment,and the mRNA expressions of hypothalamus LepR,JAK2 and STAT3 were detected by real-time quantitative polymerase chain reaction(RT-PCR),and the protein expressions of hypothalamus LepR,JAK2 and STAT3 were detected by Western Blot.Results Before treatment,compared with the normal group,the body mass of the model group,the acupoint catgut embedding group,and the acupoint catgut embedding+AG490 group were all elevated(P＜0.01),and compared with the model group,there was no significant difference in the body mass between the acupoint catgut embedding group and the acupoint catgut embedding+AG490 group(P＞0.05).After treatment,compared with the normal group,body mass,leptin and TG,TC,LDL-C levels were increased,and mRNA and protein expression levels of LepR,JAK2,STAT3 were decreased in the model group(all P＜0.01);compared with the model group,body mass,leptin and TG,TC,LDL-C levels were decreased in the acupoint catgut embedding group,and mRNA and protein levels of LepR,JAK2,STAT3 were increased in the acupoint catgut embedding + AG490 group(all P＜0.01);compared with the acupoint catgut embedding + AG490 group,the body mass,leptin and TG,TC,LDL-C levels were decreased,and mRNA and protein levels of LepR,JAK2,STAT3 were increased in the acupoint catgut embedding group(P＜0.05 or P＜0.01).Conclusion Acupoint catgut embedding has a good effect on weight loss and lipid reduction in DIO rats,and its central mechanism may be related to the down-regulation of serum leptin level and activation of hypothalamic LepR-mediated JAK2/STAT3 pathway.
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BACKGROUND:Abnormal activation of osteoclasts plays an important role in the bone destruction due to spinal tuberculosis.During the pathogenesis of osteoporosis,miR-155 knockdown activates adenosine phosphate-dependent protein kinase(AMPK)by increasing the expression of leptin receptors,thereby inhibiting osteoclast differentiation and bone resorption.However,the role of miR-155/leptin receptor(LEPR)/AMPK axis in the bone destruction due to spinal tuberculosis remains unclear. OBJECTIVE:To investigate the role and mechanism of miR-155/LEPR/AMPK axis in tuberculin-induced osteoclast formation. METHODS:RAW264.7 cells were cultured and treated with different concentrations of purified protein derivative(PPD)(1.0,2.5,5.0,10.0 IU/mL)and transfected with negative control(NC)sequence or miR-155 inhibitor,NC siRNA sequence or LEPR siRNA sequence.Tartrate resistant acid phosphatase staining was used to detect the number of osteoclasts.Fluorescence quantitative PCR was used to detect the expression of miR-155.Western blot was used to detect the expression of LEPR and p-AMPK.Double luciferase reporter gene was used to verify miR-155 targeting LEPR. RESULTS AND CONCLUSION:Compared with the control group,the number of osteoclasts and the expression level of miR-155 significantly increased,while the expression level of LEPR and p-AMPK significantly decreased in 2.5,5.0,and 10.0 IU/mL PPD groups(P＜0.05).Compared with NC+5.0 IU/mL PPD group,the number of osteoclasts and the expression level of miR-155 significantly decreased,while the expression level of LEPR and p-AMPK significantly increased in the miR-155 inhibitor+5.0 IU/mL PPD group(P＜0.05).Compared with the NC group,the fluorescence activity of LEPR wild-type double luciferase reporter gene was increased in the miR-155 inhibitor group,and decreased in the miR-155 mimic group(P＜0.05).Compared with si-NC+miR-155 inhibitor+5.0 IU/mL PPD group,the expression level of miR-155 had no significant change,the number of osteoclasts significantly increased,and the expression levels of LEPR and p-AMPL significantly decreased in si-LEPR+miR-155 inhibitor+5.0 IU/mL PPD group(P＜0.05).To conclude,tuberculin can induce osteoclast formation by increasing miR-155 expression and inhibiting downstream LEPR expression and AMPK activation.
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Objective:To investigate the effects of Danggui Shaoyao San(DSS) on cognitive function and neuronal apoptosis in vascular dementia (VD) rats.Methods:Fifty SPF grade male SD rats aged 6-7 weeks were randomly divided into sham operation group, model group, positive drug group (nimodipine group, 9.45 mg·kg -1), DSS low-dose group (1.6 g·kg -1), DSS high-dose group (6.4 g·kg -1) according to random number table, with 10 rats in each group. The VD rat model was established by permanent ligation of bilateral common carotid arteries. Seven days after modeling, the rats in different groups were administrated by gavage according to corresponding interventions, once a day, for 28 days. Morris water maze test was used to evaluate the learning and memory ability of rats.The levels of malondialdehyde (MDA), superoxide dismutase (SOD) and reactive oxygen species (ROS) in hippocampal area of rat brain were detected by ELISA.The protein expressions of apoptosis-related proteins Bcl-2, Bax, cleaved Caspase-3 and leptin receptor/glycogen synthase kinase 3β microtubule-associated protein tau(LEP-R/GSK-3β/tau) signaling pathway were detected by Western blot. GraphPad Prism 9 software was used for statistical analysis of data, repeated measure ANOVA and one-way ANOVA were used for comparison between multiple groups, and SNK- q test was used for further pairwise comparison. Results:The results of water maze experiment showed that the time and group interaction of escape latency of the five groups were not significant ( F=1.223, P>0.05), the main effect of group and time were significant ( F=74.65, 18.32, both P<0.05). On the 5th day, the escape latency of nimodipine group, DSS low-dose group and DSS high-dose group were lower than that of model group ( q=14.425, 7.477, 21.392, all P<0.05), and that of DSS high-dose group was lower than that of nimodipine group ((15.28±2.46)s, (22.78±3.31)s, q=6.966, P<0.05). There was statistically significant difference in the number of crossing platforms of rats in 5 groups ( F=17.331, P<0.05). The numbers of platform crossing in nimodipine group and DSS high-dose group were higher than that in model group ( q=6.789, 10.635, 5.270, all P<0.05), and the number of platform crossing in DSS high-dose group was higher than that in nimodipine group ((6.84±1.63), (5.22±1.75), q=3.846, P<0.05). ELISA results showed that the levels of MDA, ROS and SOD in hippocampal tissues of rats in 5 groups were significantly different ( F=49.338, 38.518, 15.440, all P<0.05). The levels of MDA and ROS in hippocampus of DSS high-dose group were lower than those of model group ( q=16.061, 13.541, both P<0.05) and nimodipine group ( q=4.317, 5.162, both P<0.05), SOD level of DSS high-dose group was higher than those of model group ( q=8.179, P<0.05) and nimodipine group ( q=4.135, P<0.05). Western blot results showed that the levels of apoptosis-related proteins Bcl-2/Bax and Caspase-3 were significantly different in the 5 groups ( F=30.692, 43.384, both P<0.01). The level of Bcl-2/Bax in DSS high-dose group was higher than that in model group ( q=10.562, P<0.05) and nimodipine group ( q=3.820, P<0.05), the level of Caspase-3 was lower than those of model group ( q=12.139, P<0.05) and nimodipine group ( q=7.734, P<0.05). The levels of LEP-R, p-GSK-3β, p-S404 tau and p-S202 tau expression level in hippocampal tissues of the 5 group were significantly different ( F=80.927, 59.230, 159.784, 105.923, all P<0.01). The levels of LEP-R and p-GSK-3β protein in nimodpine group and DSS high-dose group were higher than those in model group ( q=16.275, 20.104, both P<0.05; q=12.942, 17.257, both P<0.05), the levels of p-S404 Tau and p-S202 Tau in the two groups were lower than those in model group ( q=19.121, 27.456, both P<0.05; q=17.559, 22.780, both P<0.05). The levels of LEP-R(0.98±0.15), (0.86±0.14)) and p-GSK-3β((0.95±0.16)s, (0.82±0.13)) in DSS high-dose group were higher than those in nimodipine group ( q=3.829, 4.314, both P<0.05), the levels of p-S404 Tau((0.41±0.03)s, (0.58±0.07)) and p-S202 Tau((0.48±0.05)s, (0.59±0.06)) in DSS high-dose group were lower than those of nimodipine group ( q=8.335, 5.220, both P<0.05). Conclusion:DSS can improve the cognitive function of VD rats, and the mechanism may be related with reducing oxidative stress level, inhibiting neuronal apoptosis, and upregulating LEP-R/GSK-3β/Tau signaling pathway.
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BACKGROUND: Previous studies have showed that the alcohol extract of Morinda officinalis can effectively improve the bone quality and body mass of obese rats after ovariectomy. However, the exact mechanism is unclear. In this study, leptin and leptin receptor were used as the breakthrough point to investigate the effect of alcohol extract of Morinda officinalis on lipid metabolism and bone metabolism in ovariectomized obese rats. OBJECTIVE: To investigate the effects of alcohol extract of Morinda officinalis lipid metabolism and bone metabolism in ovariectomized obese rats. METHODS: A total of 160 SPF female Sprague-Dawley rats were randomly divided into an osteoporosis group (n=120) and a sham operation group (n=40). A postmenopausal osteoporosis model was made in the osteoporosis group by removing both ovaries. After modeling, rats in the osteoporosis group were randomly subdivided into a normal diet group, a high-fat diet group and a high-fat diet + Morinda officinalis alcohol extract group, with 40 rats in each group. The sham operation group and the normal diet group were fed with ordinary diet, while the high-fat diet group and the high-fat diet + Morinda officinalis alcohol extract group were fed with high-fat diet. The high-fat diet + Morinda officinalis alcohol extract group was gavaged with 20 g/kg Morinda officinalis alcohol extract once a day, and the remaining three groups were gavaged with 2 mL of normal saline. The study protocol was approved by the Animal Ethic Committee of Fuzhou Second Hospital of Xiamen University in September 2018 with an approval No. 20180019. RESULTS AND CONCLUSION: Compared with the sham operation group, serum leptin, leptin receptor, osteoprotegerin and high-density lipoprotein cholesterol levels were significantly lower in ovariectomized rats (P < 0.05), whereas osteocalcin, RANKL, tartrate-resistant acid phosphatase 5b, cholesterol, triacylglycerol, and low-density lipoprotein cholesterol levels were significantly higher in ovariectomized rats (P < 0.05). Compared with the high-fat diet group, serum leptin, leptin receptor, osteoprotegerin and high-density lipoprotein cholesterol levels were significantly increased in the high-fat diet + Morinda officinalis alcohol extract group (P < 0.05), whereas osteocalcin, RANKL, tartrate-resistant acid phosphatase 5b, cholesterol, triacylglycerol, and low-density lipoprotein cholesterol levels were decreased to different extents in the high-fat diet + Morinda officinalis alcohol extract group (P < 0.05). To conclusion, the alcohol extract of Morindus officinalis can up-regulate the leptin and leptin receptor expression in serum of ovariectomized obese rats, so as to improve the abnormal bone metabolism and lipid metabolism in ovariectomized obese rats.
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PURPOSE: This study aimed to investigate the clinical and metabolic determinants of circulating soluble leptin receptor (CSLR) and free leptin index (FLI) in pre-pubertal obese male children.METHODS: We conducted a preliminary cross-sectional study at three tertiary hospitals and one public primary school. Eighty obese male children without growth and developmental abnormalities aged 5–9 years were recruited. In these children, obesity was solely caused by excessive food intake, and not by acute illness, medications, endocrine abnormalities, or any syndrome. Body mass index (BMI), body fat mass, carbohydrate intake, fat intake, high density lipoprotein cholesterol level, low density lipoprotein cholesterol level, triglyceride level, and Homeostatic Model Assessment for Insulin Resistance are the potential determinants for leptin regulation, which is represented by CSLR level and FLI.RESULTS: Carbohydrate was the main source of energy. BMI and body fat mass had negative weak correlation with CSLR and positive weak correlation with FLI. Furthermore, carbohydrate intake was found to be independently associated with CSLR based on the results of the multiple linear regression analysis. Following an increase in carbohydrate intake, CSLR level decreased progressively without any negative peak.CONCLUSION: Leptin regulation in prepubertal obese male children is associated with body composition and dietary intake. Carbohydrate intake is useful for predicting CSLR. Lipid profiles and insulin resistance are not related to both CSLR and FLI. Treatment and prevention of leptin resistance in obese children should focus on reducing BMI, fat mass, and carbohydrate intake.
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Child , Humans , Male , Adipose Tissue , Body Composition , Body Mass Index , Cholesterol, HDL , Cholesterol, LDL , Cross-Sectional Studies , Diet , Eating , Growth and Development , Insulin Resistance , Leptin , Linear Models , Obesity , Receptors, Leptin , Tertiary Care Centers , TriglyceridesABSTRACT
Objective:To observe the changes of leptin receptor-tyrosine kinase Janus2 （JAK2）/signal transducer and activator of transcription 3 （STAT3） pathway and the regulatory effect of Xiaoyaosan on the hypothalamic arcuate nuclei of rats with chronic mild unpredictable stress model （CUMS）. Method:Sixty male sprague-dawley rats were randomly divided into normal group， model group， Xiaoyaosan group， and fluoxetine group. After one-week adaptive feeding， the rats in model group， Xiaoyaosan group and fluoxetine group were uesd to replicate the chronic psychological stress rat model through mild unpredictable stimulation. Meanwhile ， they were simultaneously administered the corresponding drugs， Xiaoyaosan 19.27 g·kg-1·d-1， Fluoxetine 2 mg·kg-1·d-1 （based on the average adult body weight of 60 kg）， the rats in the normal group and the model group were given the same volume of normal saline for 6 weeks. The body weight， food intake， sucrose consumption ratios， and the experimental behavior in the open field test （OFT） of the groups were observed. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） and Western blot were used to detect the expressions of ob-R， JAK2， and STAT3 in the arcuate nucleus of rat hypothalamus. Result:Compared with the normal group， the body weight and food intake of the model group were significantly decreased （P<0.05， P<0.01）， the sucrose consumption ratios ， the total behavioral distance of the experimental field and the total distance of the central area were significantly reduced， the protein and mRNA expressions of ob-R， JAK2， STAT3 in the arcuate nucleus of hypothalamus in rats increased significantly （P<0.05， P<0.01）. Compared with the model group， the body weight of Xiaoyaosan group increased significantly on the 7th， 14th， 21st and 28th days （P<0.05， P<0.01）， the food intake of rats increased significantly on the 21st and 35th days of the experiment （P<0.05）， and the sucrose consumption ratios， the total distance of the experimental behavior in the open field test （OFT） and the total distance of the central area were significantly improved. Xiaoyaosan had a corresponding regulatory effect on the protein and mRNA expressions of ob-R， JAK2， STAT3 in the arcuate nucleus of hypothalamus in model rats （P<0.05， P<0.01）. Conclusion:Xiaoyaosan regulates the body weight， appetite， and energy metabolism of chronically mild and unpredictable stress rats， which may be related to the ob-R-JAK2/STAT3 pathway in the hypothalamic arcuate nucleus.
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Objective To obtain the leptin receptor overlapping transcript-like 1 encoding gene (LepROTL1 gene) from Dermatophagoides farina, investigate the molecular characteristics of the gene and construct a prokaryotic expression vector to express this gene. Methods The LepROTL1 gene-encoding sequence fragments were captured based on the transcriptome sequencing results, and the full-length gene fragments were amplified from total RNA of D. farinae using a RT-PCR assay, and used to construct the expression plasmid pET28a(+)-LepROTL1, followed by sequencing. The plasmid was transformed into E. coli BL21 (DE3) T1R for the induction of IPTG expression. The expression product was characterized by SDS-PAGE and Western blotting. Bioinformatics analyses were performed to analyze the sequence and the molecular characteristics of its encoded protein. Results The amplification products of the RT-PCR assay showed a clear band on agarose gel electrophoresis, and sequencing analysis of the pET28a(+)-LepROTL1 plasmid showed 417 bp in length of the coding gene from the start codon ATG to the termination codon TAA. Following the plasmid transformation into E. coli and induction with IPTG, a specific band was seen on SDS-PAGE, indicating successful expression. Bioinformatics analysis showed that the LepROTL1 gene-encoded protein was composed of 134 amino acids, and had a relative molecular weight of 14 378.13 Da, a hydrophilicity index of 1.149, and certain hydrophobicity. The secondary structure was composed of alpha-helix (19 aa, 14.18%), extended strand (48 aa, 35.82%) and random coil (67 aa, 50.00%). The deduced amino acid sequence was used to obtain homologous genes by BLAST, and the phylogenetic tree showed that D. farinae was clustered with D. pteronyssinus. Conclusion The full-length sequences and expression plasmid of the LepROTL1 gene are obtained, and the molecular features of the gene are demonstrated using bioinformatics analyses, which provide insights into further studies on the gene.
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@#Introduction: The leptin receptor gene (LEPR) variation plays an important role in diseases related with obesity which include Type 2 Diabetes Mellitus (T2DM) and hypertension in some populations. The role of this variation is still controversial and not yet studied in the eastern parts of Indonesia. Hence, this study aimed to explore the correlation of leptin receptor variations (Lys109Arg and Gln223Arg) with blood pressure and blood glucose in T2DM in Ternate population. Methods: This study examined 136 subjects with the age range of 32-76 years old. Five mL of fasting blood were taken to determine blood glucose levels using the GOD-PAP method, and leukocytes were used for genotyping by polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) technique methods. Frequencies of genotypes and alleles were analyzed with chi square tests. Correlations of genotypes with the anthropometric measurements were calculated by logistic regression with significance value if p<0.05. Results: Variation of Lys109Arg LEPR gene did not influence the Body Mass Index (BMI), blood pressure, nor blood glucose level. Variation of Gln223Arg LEPR gene also did not influence BMI and blood glucose level, but correlated with blood pressure. Regression analysis after adjusted for age, gender, BMI and blood glucose level showed that this variation remains significantly different. Conclusion: Variation of Gln223Arg LEPR gene correlated with blood pressure but variation of Lys109Arg LEPR gene was not correlated with blood glucose level nor blood pressure. Future study is needed to correlate other genes and examine their effect on metabolic syndrome diseases.
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Abstract INTRODUCTION: Leptin (LEP) is a peptide hormone that acts via leptin receptor (LEPR) binding. Genetic evidence from different human populations has implicated LEP/LEPR in the pathogenesis of coronary artery disease (CAD), and suggests that certain LEP/LEPR gene polymorphisms may increase the risk of CAD. The aim of this study was to assess two single nucleotide polymorphisms (SNPs) in LEP genes (rs2167270 and rs7799039) and two in LEPR genes (rs6588147, rs1137100) for association with CAD. METHODS: We enrolled 271 North Chinese Han CAD patients, and 113 healthy age- and sex-matched controls. Genomic DNA was extracted from whole blood, and the four SNPs were assessed using a MassArray system. RESULTS: The G allele frequency at rs2167270 was significantly higher among CAD cases than among controls. The AG genotype at rs7799039 was associated with a significantly decreased risk of CAD unlike the AA genotype used as the reference. The A allele was significantly associated with the CAD patient group. Interestingly, statistically significant differences in genotype and allele frequency at LEP rs2167270 and rs7799039 existed among females but not among males. CONCLUSIONS: The current study detected a significant association between genetic variations at LEP rs7799039 and rs2167270 and the risk of CAD in a north Chinese population, and revealed that LEP rs2167270 and rs7799039 gene polymorphisms might act as predisposing factors for CAD.
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Humans , Male , Aged , Coronary Artery Disease/genetics , Leptin/genetics , Receptors, Leptin/genetics , Body Mass Index , Case-Control Studies , Risk Factors , Genetic Predisposition to Disease , Polymorphism, Single Nucleotide/genetics , Gene Frequency , Genotype , Middle AgedABSTRACT
This study reported two women with extreme obesity who underwent metabolic surgery due to their mutations in leptin receptor (LEPR).Genomic DNA was extracted from the anticoagulant blood samples of the two patients and their parents.A panel of genes related to metabolic diseases or whole exon sequencing was screened and the results were confirmed by Sanger sequencing.This is the first time that these three mutations in LEPR were reported.Two patients complained insatiety and early-onset obesity since childhood at clinics.Patient 1 was a 39-year-old woman with height 150 cm,weight 130 kg,and BMI 57.8 kg/m2.Serum leptin level was 156.4 μg/L.A homozygous mutation of c.2317G＞T was found in exon 15 of LEPR gene in patient 1,which was descended from her father and mother respectively.Patient 2 was a 37-year-old woman with height 158 cm,weight 167 kg,and BMI 67 kg/m2.Serum leptin level was 193.4 μg/L.Genetic analysis showed compound heterozygous mutations of c.1482delT and c.1892C ＞ A.Her father showed heterozygous c.1482delT mutation,and her mother carried heterozygous c.1892C ＞ A mutation.Two patients all underwent metabolic surgery with body weight reduction of about 22 kg and 40 kg respectively after first six months.However,the follow-up studies showed that the body weight of patient 1 rebounded to pre-surgery level in two years and patient 2 did not further lose weight in the following six months.
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Objective@#To explore the association between plasma leptin (LEP) levels, soluble leptin receptor(SLR), free leptin index and breast cancer.@*Methods@#245 new female cases of primary breast cancer confirmed by histopathology examination were sequentially recruited into the study. A total of 245 age-matched healthy women were enrolled as controls during the same period. A standardized questionnaire was used to collect the demographic information of the subjects. Blood samples were collected and the levels of LEP and SLR in plasma were measured by enzyme linked immunosorbent assay. The differences of LEP, SLR and FLI expression between control and cases group, as well as different breast cancer subtypes and TNM stages were compared using t-test and ANOVA after stratification by menopause status. Multivariate logistic regression was used to explore the contributions of the three indexes to the risk of breast cancer.@*Results@#Females in both cases and control group were (50.7 ± 9.4) years old. The level of SLR and FLI (P50(P25,P75)) in premenopausal women were 18.4 (11.2, 28.7), 0.5 (0.4, 0.6) μg/L in case group and 27.7 (19.2, 43.4), 0.3 (0.3, 0.4) μg/L in control group (P<0.001). While the level of postmenopausal women in case group were 20.3 (12.8, 31.8), 0.5 (0.4, 0.6) μ g/L (P<0.001), and 30.1 (18.8, 40.5), 0.3 (0.3, 0.5) μg/L in control group (P<0.001), respectively. After adjustment for confounding factors and BMI, the relationship between FLI and breast cancer remained significant for both pre- and postmenopausal women while the association between SLR and breast cancer was significant only in premenopausal women. Compared with the lowest level of SLR, higer levels of SLR is associated with a reduced risk of breast cancer (premenopausal women, OR=0.10, 95% CI: 0.04-0.29, Ptrend<0.001). Compared with the lowest level of FLI, FLI at higher levels is associated with an increased risk of breast cancer (premenopausal women, OR=7.14, 95% CI: 2.86-17.83, Ptrend<0.001; postmenopausal women, OR=8.10, 95% CI: 2.85-22.98, Ptrend<0.001). No significant association between LEP and breast cancer or association between the three indexes and breast cancer subtypes and TNM stages was found (P>0.05).@*Conclusion@#SLR may be a protective factor for breast cancer while FLI may increase the risk of breast cancer.
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Objective To clarify the expression of leptin and leptin receptor in normal brain tissues and gliomas and investigate the effect of exogenous leptin on the proliferation,migration and invasion of human glioma U251 cell line.Methods Immunohistochemical staining was used to detect the expression of leptin and leptin receptor in 50 cases of different grades of glioma tissues and 20 cases of normal brain tissues.The effects of exogenous leptin on proliferation,migration and invasion of U251 cells were detected by MTT assay,cell scratch assay and Transwell invasion assay.Results (1) The positive expression rates of leptin and leptin receptors in glioma tissues were 50.0％ and 92.0％,respectively.(2)Proliferation activity:leptin concentrations of 0 ng/ml,10 ng/ml,and 50 ng/ml had no significant difference in the proliferation of U251 cells (absorbance:0.263±0.015,0.273±0.017 and 0.277±0.006,respectively),and the leptin concentration of 100 ng/ml had a significant effect on the proliferation of U251 cells (absorbance:0.315±0.005,P＜0.05).(3)Migration ability:the migration rate of U251 cells treated with different concentrations of leptin increased significantly with the passage of time,and the migration rate was most significant at the concentration of 100 ng/ml ((93.313±3.080) ％),and the difference was statistically significant (P＜0.05).(4)Invasive ability:with the increase of leptin concentration and the prolongation of the action time,the invasive ability of U251 cells was enhanced.When leptin was used at a concentration of 100 ng/ml,the number of penetrating cells were the biggest(135±2).Conclusion Leptin and leptin receptors are involved in the occurrence of gliomas;and exogenous leptin promotes the proliferation of U251 cells and has time and dose dependability on the migration and invasion of U251 cells.
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A leptina, uma citocina produzida pelas células adiposas, é alvo da comunidade científica por acreditarem que ela apresente impacto sobre a reprodução dos animais promovendo a puberdade, foliculogênese e oogênese, ciclo estral e auxiliando na fecundação. A compreensão dos mecanismos que controlam a atividade reprodutiva de preás (Galea spixii) possui papel relevante para a preservação da espécie. Desta forma, o presente trabalho propôs analisar a imunolocalização dos receptores de leptina (Ob-R) no ovário de preás. Coletaram-se os ovários de 20 fêmeas adultas, não prenhes e saudáveis. As amostras foram fixadas em paraformaldeído a 4% em tampão fosfato, incluídas em parafina e seccionadas para a realização de imunohistoquímica (IHC). As secções foram fotomicrografadas e avaliadas quanto à intensidade da reação. Observou-se forte imunorreação no oócito e nas células da teca, moderada nas células do estroma ovariano e nas células luteínicas grandes e fracamente coradas nas células da granulosa, endoteliais, perivasculares e células luteínicas pequenas. Quando comparado a expressão de receptores ao longo do desenvolvimento folicular foi observado que o oócito e as células da teca se mantiveram com expressão na mesma intensidade. Entretanto, as células da granulosa apresentaram forte marcação nos estádios pré-antrais enquanto que nos folículos antrais apresentou fraca intensidade. Concluímos que em ovários de Galea spixii existe a presença de Ob-R nas principais estruturas do ovário sugerindo que este hormônio desempenhe papel fundamental na reprodução desta espécie.
Leptin, a cytokine produced by adipose cells, is the target of the scientific community for believing that it has an impact on the reproduction of the animals promoting puberty, folliculogenesis and oogenesis, estrous cycle and aiding in fertilization. The understanding of the mechanisms controlling the reproductive activity of Spix's Yellow-toothed Cavy (Galea spixii) plays a relevant role in the preservation of the species. Thus, the present study proposed to analyze the immunolocalization of leptin receptors (Ob-R) in the ovary of cavies. Ovaries from 20 adult, non-pregnant, healthy females were collected. The samples were fixed in 4% phosphate buffered paraformaldehyde, embedded in paraffin and sectioned for immunohistochemistry. The sections were photomicrographs and intensity of the reaction was measured. Strong immunoreaction was observed in oocyte and theca cells, moderate in ovarian stromal cells and large luteal cells and weak stained in granulosa, endothelial, perivascular and small luteal cells. When compared to receptor expression along follicular development it was observed that the oocyte and the theca cells remained with expression at the same intensity. However, the granulosa cells presented strong stained in the preantral stages, whereas in the antral follicles it presented low intensity. We conclude that in the ovaries of Galea spixii there is the presence of Ob-R in the main structures of the ovary sugesting that this hormone plays a fundamental role in the reproduction of this species.
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Animals , Oogenesis , Receptors, Leptin/analysis , Guinea Pigs/physiology , Rodentia/embryologyABSTRACT
Introdução: A obesidade consiste em um complexo conjunto de fatores comportamentais, ambientais e genéticos que se relacionam e se potencializam. Acredita-se que polimorfismos de nucleotídeo único (SNPs) possuam relação com a obesidade e que estejam hiperexpressos nesta condição. Objetivo: Revisar a relação da presença de polimorfismos no gene LEPR com a obesidade em crianças e adolescentes, buscando evidenciar condições e/ou fatores ambientais relacionados. Métodos: Trata-se de um artigo de atualização sobre o tema polimorfismo do LEPR e a associação com a obesidade. Resultados: Os dados levantados mostram a influência de polimorfismos do gene receptor de leptina (LEPR) com o desenvolvimento da obesidade, assim como fatores ambientais, tais como dieta hipercalórica na presença do polimorfismo, potencializam o desenvolvimento dessa condição clínica, resultando em aumento das medidas antropométricas e bioquímicas, na presença da mutação genética.
Introduction: Obesity consists of a complex set of behavioral, environmental and genetic factors that relate to and potentiate. It is believed that single nucleotide polymorphisms (SNPs) have relation with obesity and are hiperexpressos this condition. Objective: Review the relationship between the presence of polymorphisms in LEPR gene with obesity in children and adolescents, to disclosing conditions and / or related environmental factors. Methods: This is an update article on the topic LEPR polymorphism and the association with obesity. Results: The data collected show the influence of polymorphisms of the Leptin receptor gene (LEPR) with the development of obesity as well as environmental factors such as caloric diet in the presence of the polymorphism potentiate the development of this medical condition, resulting in increase of action anthropometric and biochemical in the presence of gene mutation.
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Leptin participates in the whole process of pregnancy.Soluble leptin receptor has close relationship with metabolic syndrome, type 2 diabetes.Leptin can two-way regulate insulin through different signal transduction pathways.Gestational diabetes influence maternal glucose metabolism and lipid metabolism.Soluble leptin receptors adjust the utilization rate and the concentration of leptin.It can increase the leptin sensitivity and indirectly involve in the body′s endocrine metabolism process.This article reviews the change of leptin and soluble leptin receptor during the pregnancy and the feasibility as early gestational diabetes screening index.
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Objective:To investigate the relationship of polymorphism of leptin receptor gene Gln223Arg with asthma and metabolic syndrome.Methods: Collected 120 asthma patients,92 metabolic syndrome patients,54 asthma combined metabolic syndrome patients and 81 normal controls.According to the severity,the asthma patients were divided into mild-medium group and severe group.The serum leptin level was measured by ELISA,the genotypes of leptin receptor were analyzed by the method of polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP),and statistcs of each subject′s MBI,blood pressure,lung function and fasting blood glucose were collected.Results: ①There were significant differences in genotype and allele frequency in leptin receptor gene Gln223Arg between the metabolic syndrome group,asthma combined metabolic syndrome group and normal control group(P<0.05).②The allele frequency and genotype in leptin receptor gene Gln223Arg were significant different between the severe asthma group and normal control group(P<0.05).③The serum leptin level,BMI and systolic blood pressure of AA+AG genotype group were significiant higher than GG genotype group(P<0.05),while the value of FEV1% and FEV1/FVC of lung function were lower than GG genotype group(P<0.05).Conclusion: Leptin receptor gene Gln223Arg polymorphism is correlated with asthma and metabolic syndrome,and by causing leptin resistance,the A allele might be the genetic factor that contribute to individual susceptibility for asthma and metabolic syndrome.
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La obesidad resulta de los efectos combinados de los genes, el ambiente y el estilo de vida. La leptina (LEP) y el receptor de leptina (LEPR) son genes que han sido evaluados en la búsqueda de variantes que podrían estar relacionadas con la obesidad y sus complicaciones cardiometabólicas. Objetivo: Evaluar la posible asociación entre los polimorfismos G2548A del gen LEP y Gln223Arg del gen LEPR con el desarrollo de obesidad y resistencia a la insulina (RI) en niños y adolescentes pre-púberes. Métodos: Se estudiaron 314 niños de 2-11 años, clasificados según los parámetros antropométricos y bioquímicos en: a) sobrepeso/obesos sin RI (n=133), b) sobrepeso/obesos con RI (n=75) y c) controles sanos (n=70). La genotipificación fue realizada por reacción en cadena de la polimerasapolimorfismos de longitud de fragmentos de restricción (PCR-RFLP); se estudiaron las asociaciones entre genotipo y riesgo, y se compararon los promedios de las medidas antropométricas y bioquímicas. Resultados: La frecuencia genotípica para el polimorfismo G2548A del gen LEP fue 51% G/A, 33% G/G y 16% A/A; para el polimorfismo Gln223Arg del gen LEPR fue Gln/Arg 49%, Gln/Gln 31% y Arg/Arg 20%. Se encontró diferencia significativa en la distribución de los diferentes genotipos del gen de LEPR en los niños con sobrepeso/obesidad y RI con respecto al grupo control (OR= 2,6; IC 95%=1,17-5,75; p < 0.05). Conclusión: Se observó una asociación entre la presencia del genotipo Gln/Gln del gen LEPR con la RI (factor de riesgo cardiometabólico), presentando los niños con sobrepeso/obesidad y RI 2,6 veces más riesgo a presentar RI.
Obesity is a result of the combined effects of genes, environment and lifestyle. The Leptin (LEP) and leptin receptor (LEPR) are genes that have been extensively evaluated in search for variants that may be associated with obesity and cardiometabolic complications. Objective: To evaluate the possible association between polymorphisms G2548A of the LEP gene and Gln223Arg of the LEPR gene with the development of obesity and insulin resistance (IR) in prepubertal children and adolescents. Methods: We studied 314 children 2-11 years, grouped by anthropometric and biochemical parameters: a) overweight /obese without IR (n = 133), b) overweight /obese with IR (n = 75) and c) healthy controls (n = 70). Genotyping was performed by Polymerase Chain Reaction-Restriction Fragment Length Polymorphisms (PCR-RFLP) method. Genotype-risk associations were studied. We then compared the average values for anthropometric and biochemical parameters. Results: The genotypic frequency for polymorphism G2548A of LEP gene was 51% for the G/A genotype, 33% G/G and 16% A/A genotype; for polymorphism Gln223Arg of LEPR gene was of Gln/Arg 49%, Gln/Gln 31% and Arg/Arg 20%. Significant difference was found in the distribution of different genotypes of the LEPR gene in children with overweight/obesity with IR compared to the control group (OR = 2.6; 95% CI = 1.17 to 5.75; p < 0.05). Conclusion: We observed an association between the presence of Gln/Gln genotype of the LEPR gene with insulin resistance (cardiometabolic risk factor) children, rendering these children with overweight/obese with IR 2,6 times more likely to be with insulin.
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The C57BLKS/J-Lepr(db) mouse has a point mutation in the leptin receptor gene and is one of the most useful animal model for non-insulin dependent diabetes mellitus in human. Since the homozygote of C57BLKS/J-Lepr(db) mouse is infertile, detection of point mutation in the leptin receptor gene is important for efficient maintaining strains as well as mass production of homozygotes. To develop a rapid and efficient genotyping method for C57BLKS/J-Lepr(db) mouse, the tetra-primer amplification-refractory mutation system polymerase chain reaction (ARMS-PCR) was used. The 407 and 199 bp PCR products were amplified from normal (+/+) mice; while the 407 and 268 bp PCR products were amplified from homozygotes (db/db) mice; and the 407, 268, and 199 bp PCR products were amplified from heterozygotes (db/+) mice. This result showed that the tetra-primer ARMS-PCR analysis by us is suitable to detect point mutation of the leptin receptor gene. Taken together, our method will dramatically reduce animal use for maintenance of strains as well as production of homozygote in the C57BLKS/J-Lepr(db) strains.
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Animals , Humans , Mice , Diabetes Mellitus , Heterozygote , Homozygote , Leptin , Models, Animal , Point Mutation , Polymerase Chain Reaction , Receptors, LeptinABSTRACT
Objective To investigate the correlation between leptin receptor(LEPR)gene Gln223Arg variation with metabo-lism syndrome and its influence on ambulatory blood pressure .Methods Totally 167 patients with metabolism syndrome were se-lected and contemporaneous 216 individuals undergoing the physical examination were selected as the control group .The blood pres-sure ,ambulatory blood pressure ,biochemical indicators and insulin were detected in all the subjects .The DNA polymorphology a-nalysis was performed by adopteint PCR—restricted fragment length polymorphism(RFLP) .The Gln223Arg genotype was judged by electrophoresis and sequencing .Results Three genotypes of AA ,GG and AG were detected .The frequency of carrying A alleles in the metabolism syndrome group was significantly higher than that in the control group .The occurrence risk of metabolism syn-drome and non—dipper type blood pressure rhythm for carrying allele A was 3 .302 times(P=0 .000;95% CI:2 .432 —4 .483)and 2 .506 times of carrying allele G(P=0 .000 ;95% CI:1 .566 —4 .008) .The patients with AA genotype had higher BMI ,blood pres-sure ,blood glucose and fasting insulin levels ,more serious dyslipidemia ,greater waist circumference and higher insulin resistance in-dex .The patients with metabolism syndrome carrying A allele also had higher ambulatory blood pressure indexes .Conclusion LEPR gene Gln223Arg polymorphism A allele carrier has the great risk for metabolism syndrome occurrence ,higher ambulatory blood pressure ,moreover is more inclined to non—dipper type blood pressure rhythm .
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<p><b>INTRODUCTION</b>The aim of this study was to determine the effect of a high-fat diet (HFD) on oocyte maturation and quality in a mouse model.</p><p><b>METHODS</b>Female BALB/c mice were allocated to one of the following groups: (a) control group (n = 40), which received a controlled diet; or (b) HFD group (n = 40), which received an HFD for 12 weeks. Sections of the ovary were examined histologically. The number of follicles and corpora lutea were counted. In vitro maturation and in vitro fertilisation (IVF) were assessed in germinal vesicle (GV) and metaphase II (MII) oocytes, respectively. The expression of bone morphogenetic protein 15 (BMP15) and leptin receptor genes in GV and MII oocytes was evaluated using reverse transcription real-time polymerase chain reactions.</p><p><b>RESULTS</b>In the HFD group, there was a decreased number of primordial and Graafian follicles, as well as corpora lutea (p < 0.05). The rate of oocyte development to the MII stage was also reduced (p < 0.001). Cumulus expansion was observed more frequently in the control group than the HFD group (p < 0.05). The IVF rate in the HFD group was lower than that in the control group (p < 0.05). In the HFD group, BMP15 and leptin receptor genes were upregulated in the GV stage (p > 0.05) and MII stage (p < 0.05), compared to the control group.</p><p><b>CONCLUSION</b>An HFD reduces folliculogenesis in the primordial and Graafian stages, in vitro maturation and in vitro fertilisation rates, as well as oocyte quality in mice.</p>